Wellhead apparatus



C. C. BROWN Nov. 24, 1953 WELLHEAD j APPARATUS Filed Dec. 17, 1951 3Sheets-Sheet l (were C. Brown INVENTOR.

by M1 ATTORNEYJ Nov. 24, 1953 c. c. BROWN WELLHEAD APPARATUS 3Sheets-Sheet 3 Filed Dec. 17 1951 1 C/ce ro C. Brown Patented Nov. 24,1953 UNITED STATES ATENT OFFICE WELLHEAD APPARATUS Cicero Brown,Houston, Tex. Application December 11 1951, Serial No. 262,014

14 Claims. 1

This invention relates to new and useful improvements in well headapparatus.

One object of the invention is to provide an improved well headapparatus which is so constructed that the well tubing which issuspended from the apparatus may be either rotated or movedlongitudinally, as conditions require, whereby various well operationsand the setting of well tools ma be accomplished after the tubing hasbeen landed.

An important object of the invention is to provide an improved well headassembly for landing and supporting a well tubing string and beingarranged so that only metallic seals are exposed to the well pressureswhen the tubing is in its final position.

Another object is to provide an improved tubing head assembly whichincludes a swivel mounting for the tubing string whereby a rotativeupward tension on the tubing string to obviate leaks at the variouscouplings and joint connections of the tubing string.

Another object is to provide an improved well head apparatus which isparticularly adapted for use in carrying out the well completion methoddisclosed in my co-pending application, Serial No. 202,174, which methoddiscloses actuation of well tools by means of rotation of the tubingstring.

A still further object is to provide an apparatus of the characterdescribed which will allow rotation or reciprocation, or both, of thetubing string, after the tubing has been landed and which is constructedso that the tubing may be lowered and landed through the usual blowoutpreventers and other pressure control equipment, whereby well completionmay be carried out with the benefit of blowout protection devices inplace, as is the usual practice.

The construction designed to carry out the invention will be hereinafterdescribed together with other features thereof.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawingsforming a part thereof, wherein an example of the invention is shown,and wherein:

Figure 1 is a schematic view illustrating the improved tubing headforming part of the present invention and showing the tubing stringbeing lowered within the well through a blowout preventer,

Figure 2 is a similar view showing landing of the tubing hanger,

Figure 3 is a similar View with the blowout preventer and controlequipment removed from the tubing head,

Figure 4 is a view similar to Figure 3 showing the lower valve of aChristmas tree assembly connected with the tubing head,

Figure 5 is an enlarged vertical sectional view of the improved wellhead apparatus illustrating the parts in position after landing of thetubing hanger,

Figure 6 is a view similar to Figure 5 showing the actuating stem movedupwardly with respect to the hanger with a tension pulled on the tubingstring, and

Figure 7 is a sectional detail illustrating the manner of removal of thecheck valve which normally closes the bore of the tubing string duringthe lowering and landing of said string.

In the drawings the numeral Ill designates a casinghead which is mountedon the last string of easing extending downwardly into the well bore(not shown). A tubing head H provided with a base flange l2 (Figure 5)is bolted to the upper flange of the casinghead and is provided with anaxial bore l3 from which the usual side outlets I4 extend. An upperflange I5 is formed on the tubing head body for connection with controlequipment during lowering and running of tubing within the well bore. Aplurality of radial lock screws it, only one of which is illustrated,are provided in the flange and are arranged to project inwardly into theupper end of the bore of the tubing head body. A sealing plug ll closesthe outer end of the open ng in which each locking screw is mounted. Theflange also has a radial test port is normally closed by a plug I9.Within the upper portion of the bore 13 of the tubing head is an annularseat 20 which is adapted to receive a hanger assembly generallyindicated by the letter A in Figure 5, as will be explained.

The tubing head H is assembled above the casing head i e and as shown inFigure 1, a blowout preventer B is mounted above the tubing head. Abovethe blowout preventer is usually a second blowout preventer and a mastergate valve, neither of which is shown because this is standard blowoutprevention equipment. The hanger assembly A includes a tubular stem 21which has its lower end threaded into a coupling 22 and said coupling isthreaded onto the upper end of the tubing string 23. A lowering pipe 2%is adapted to thread into the upper end of the hanger assembly A,whereby the tubing and the hanger may be lowered downwardly through theblowout preventer equipment to engage the seat 28 Within the tubing headII. This lowering operation is clearly illustrated in Figures 1 and 2,the latter showing the hanger assembly seated within the tubing head.

After the assembly is seated the lock screws G are utilized to lock saidhanger upon the seat, and as will be hereinafter explained, the tubingbore is closed at this time. is locked down by the lock screws theblowout preventer equipment above the tubing head may be removed and ahold-down flange 25 may be substituted therefor, such hold-down flangebeing secured to the u per flange l5 of the tubing head by bolts 26.Thereafter the lowering pipe 24 is removed from the hanger assembly andthe usual Christmas tree is then connected with the flange 25, asclearly shown in Figure 4. The entire Christmas tree is not shown sincethis is standard ecuipment and onl the lower valve '25 of said Christmastree is illustrated. The connection between the Christmas tree and theflange 25 may be made through the usual flanged riser 21. i

The particular hanger assembly A is clearly shown in Figures 5 and 6 andincludes a hanger body 28 having an inclined seating surface 29 which isadapted to engage the annular seat 28 within the tubing head. Suitablepacking rings 30 which may be the usual O-ring type of packing aremounted in external grooves in the seating surface 29 and function toeffect a pressure type seal at this point. An annular groove 3! isformed in the hanger body and when said hanger is in a seated positionthis groove is opposite the locking screws I5 whereby said screws may bemoved inwardly into engagement with the groove to thereby lock the bodyagainst upward displacement. When the hanger body is seated the groove3! is also opposite the test When the hanger port l8 so that a testingof the seals may be effected in the usual manner.

The hanger body 28 is formed with an integral depending extension 32 andsaid extension has its bore recessed to receive chevron type packing 33which is retained in place by a flanged packing gland 3d.

lower end of the bore of the gland 34 is formed with an inclined annularseating surface 37.

The tubular stem 2! which forms part of the hanger assembly extendsdownwardly through the hanger body and the extension, as well as throughthe packing gland 34, and has the coupling 22 secured to its lower end.The upper end of the coupling 22 is formed with an inclined surface 33which is adapted to engage and seat within the lower end of the gland34, the surface 38 contacting and maintaining sealing engagement withthe seat 31 of said gland.

For imparting a rotative movement or a longitudinal movement or both tothe sealing stem 2 to impart similar movement to the tubing 23, theupper portion of said stem is enlarged and provided with coarse threads39 which may be An O-ring type packing 35 is mounted within a suitablegroove of the bore of either left or right hand threads. Above thethreads the stem is formed with a flange 86 whereby, if desired, theChristmas tree may be attached directly to the stem instead of to theretaining flange 25. The threads 39 are adapted to interengage withthreads 5! formed Within the bore of a rotatable actuating nut 4 2. Thethreads 4! will of course be in the same direction as the threads 35,and likewise maybe either lef or right hand threads. As is clearly shownin Figure 5, the nut 42 is mounted upon ball bearings 43 which aredisposed within a raceway "64 formed in the upper surface of the hangerbody 28. Upward displacement of the rotatable actuating nut 42 isprevented by a retaining collar 45 which has its upper end overhangingan external shoulder 46 formed on the nut; the re taining collar isthreaded onto the upper end of the hanger body and thereby retains theactuating nut as part of the assembly. A suitable O-ring packing A?seals oil between the retaining collar and actuating nut, while sealingmaterial 48 is interposed between the bore of the nut and the threads ofthe actuating stem to seal off the thread connection. Two or morerecesses 49 may be formed in the exterior of the actuating nut forreceiving a spanner wrench to impart rotation to the nut.

When the hanger assembly A is seated within the tubing head, asillustrated in Figure 5, and the blowout preventer equipment has beenremoved, an additional seal between the hanger body 28 and the tubinghead body is effected by a sealing ring 50. This sealing ring is of aninverted U-shape in cross-section and engages within a groove 5!provided in an external shoulder on the hanger body as well as within agroove 52 formed in the upper surface of the tubing body. The flange 25rests upon the upper surface of the sealing ring 59 and functions tohold the same in sealing position.

In the operation of the apparatus, the hanger assembly A has its tubularstem 2! connected through the coupling 22 with the tubing 23. back checkvalve 53 (Figures 5 and 7) having an upwardly closing ball check 54 isconnected in left hand threads 55 formed within the upper end of thetubular stem 2! of the hanger assembly. This ball check functions toclose the bore of the tubing during lowering and landing of the tubing.Right hand threads 56 provided above the threads 55 receive the lowerend of the lowering pipe 24.

The tubing head H is mounted on the casing head, as shown in Figure 1,with the blowout preventer equipment mounted thereabove. By means of thelowering pipe 24 the last portion of the tubing 23 and the hangerassembly A are lowered through the blowout preventer until the inclinedseating surface 29 of the hanger body 23 engages the seat 2E! of thetubing head. Upon reaching this position the lock screws I 6 areoperated to engage the annular groove 3! in the hanger, and thus thehanger is locked down within the tubing head. The hanger functions toseal the annular space between the tubing and the casing while the backcheck valve 53 closes the bore of the tubing against upward flow. It isthus possible to remove the blowout preventer equipment from above thetubing head and when this is done the sealing ring 5@ is placed inposition between the hanger body 28 and the tubing head body; the flange25 is then bolted in position to the upper flange of the tubing head andthereon which is to be set down the hole to pack off between the tubingandthe casing in the usual manner, and such packer may be of a con--struction which will set the same upon a rotation of the tubing string.In order to effect the seating of the packer it is only necessary toimpart a simultaneous rotation to the sealing stem 2i and actuating nut12, this rotation being possible when the actuating nut is abutting theflange Ml of the sealing stem and the nut or stem is turned. in adirection such that the nut and stem tend to thread toward each other.For example, if threads 39 and 4| are right hand threads, the stem 25 isturned to the right or clockwise, or the nut 42 is turned to the left orcounter-clockwise to effect the simultaneous rotation of the nut andstem. The simultaneous rotation of the nut 52 and the stem 2! issubstantially frictionless since the nut 42 is mounted upon the ballbearings 43. The rotation of the sealing stem 2! with a simultaneousrotation of the actuating nut 42 will impart a rotative movement to thetubing to effect a setting of the packer or to effect the operation ofany well tool mounted on the tubing which will be actuated throughrotation. At this time there is a metal to metal seal between the hangerbody 28 and the seat 29! of the tubing head. Sealing off around the stem2! is effected by the O-rings 35 and 36, as well as by the chevronpacking 33. After the packer or other well tool has been operatedthrough a rotation of the tubing, it is then desirable to pull an upwardtension upon the tubing. It has been found that particularly in the caseof older tubing such upward tension is necessary to prevent a leakage atthe connecting collars of the tubing string. To accomplish the upwardmovement of the tubing to pull a tension thereon, it is only necessaryto rotate the actuating nut 2 with respect to the tubular stem 2!. Suchindependent rotation of the nut 42 relative to the stem results in theinterengaging threads 39 and ll efiecting an upward movement of thestem. The actuating nut 42 is of course held against upward displacementby the retaining collar 45 and when the threads 39 and M are right handthreads, upon a rotation of the nut 42 to the right or clockwise, thecoaction between the threads produces an upward travel of the stem. Thelower portion of the tubing will, of course, be held stationary by thesetting of the packer and the upward movement of the upper end of thetubing will pull a tension on the entire tubing string. Upward movementof the tubular actuating stem 2| continues until the parts assume theposition shown in Figure 6, at which time the beveled upper end 38 ofthe coupling collar 22 engages the inclined seat 31 at the lower end ofthe gland 34. The engagement of these parts produces a metal to metalseal which seals ofl between the bore of the tubing and the hanger. Itis thus apparent that in final position only metal to metal seals areexposed to the well pressures and the difficulties which are encountereddue to the ordinary flexible packing being exposed to well pressures areobviated.

After the apparatus has been actuated, the Christmas tree C is connectedeither to the flange 25, as illustrated in Figure 4, or is connected tothe upper flange Ml of the stem 2| of the assembly. As is the usualpractice the Christmas tree has a lubricator at its upper end so that aretrieving tool generally indicated at in Figure '7 may be employed forremoving the closure 53 from the tubing. The retrieving tool 60 isthreaded into the upper end of the valve or closure 53 with a connectionbeing made by right hand threads 6!. Since the threads SI which mountthe valve within the stem 2! are left hand threads the tool may beemployed to remove the valve or closure, after which the well may beplaced on production with control being through the usual Christmas treeand other valved connections.

From the foregoing it will be evident that a simple and effective typeof well head apparatus is provided. The unit is so arranged that it maybe lowered and landed through the usual control equipment in accordancewith general practice; after the hanger assembly is in place theapparatus may be manipulated to impart a rotation to the tubing or toimpart longitudinal movement to the tubing so that any of the well knowntype of well tools may be set within the well casing. After setting, anupward longitudinal movement of the tubing may be carried out to pulland maintain a tension on the tubing string. The sealing arrangement ofthe assembly is such that only metal to metal seals are exposed to thewell pressure so that the difiiculties encountered with exposure offlexible packing to such pressures are eliminated. V The foregoingdisclosure and description of the invention is illustrative andexplanatory thereof and various changes in the size, shape andmaterials, as well as in the details of the illustrated construction maybe made, within the scope of the appended claims, without departing fromthe spirit of the invention.

Having described the invention, I claim:

1. A well head apparatus including, a tubing head, a hanger assemblysupported within said tubing head and including a hanger body seated insaid tubing head, means forming part of said hanger assembly dependingfrom said hanger body and connected with a well tubing for suspendingsaid tubing, and means for mounting saidlast named means for rotationand longitudinal movement of said well tubing with respect to the hangerbody.

2. A well head apparatus including, a tubing head, having a supportingseat, a hanger engageable with and supported upon said seat, a tubularstem element mounted within the hanger and having its lower enddepending therefrom and connected with a well tubing, and means formounting the tubular element for rotation and longitudinal movement ofsaid well tubing with respect to the hanger.

3. A well head apparatusincluding, a tubing head, having an annular seatwithin its bore, a tubular hanger having an external seating surfaceengageable with said seat, whereby the hanger is supported within thehead, means extending laterally through the head and adapted to engagethe hanger for locking said hanger in seated position within the head, atubular stem extending axially through the hanger and having its lowerend connected with a well tubing, and means mounting the tubular stemfor rotation and axial movement of said well tubing with respect to thehanger and tubing head.

4. A well head apparatus including, a tubing head, having an annularseat within its bore,

a tubular hanger having'an externallseating surface engageable with saidseat, whereby the hanger is supported within the head, means extendinglaterally through the head and adapted to engage the hanger for lockingsaid hanger in seated position within the head, a tubular stem extendingaxially through the hanger and having its lower end connected with awell tubing, an annular actuating member surrounding the stem androtatably mounted on the upper end of the hanger, and interengagingmeans on the actuating member and stem for imparting longitudinalmovement to said stem upon a rotation of said member.

5.. A well head apparatus including, a tubing head, having an annularseat within its bore, a tubular hanger having an external seatingsurface engageable with said seat, whereby the hanger is supportedwithin the head, means extending laterally through the head and adaptedto engage the hanger for locking said hanger in seated position withinthe head, a tubular stem extending axiall through the hanger and havingits lower end connected with a well tubing, an annular actuating memberrotatably mounted on the upper end of the hanger and surrounding thestem, and interengaging threads on the stem and member whereby rotationof the member independently of the stem imparts a movement to the stemaxially of said member and said hanger. 1

6. A Well head apparatus asset forth in claim 5, together with anenlargement on they stem below the hanger and movable intosealingcontact with the lower end of the hanger when the stem is movedto its limit of upward movement with respect to the hanger.

7. A well head apparatus including, a tubing head having an internalseat, a tubular hanger supported upon said seat, an annular actuatingmember rotatably mounted on the upper end of the hanger, a tubular stemextending through the actuating member and hanger and having its lowerend projecting below the hanger and connected with a well pipe, a coarsethread eonnection between the stem and actuating member, wherebyrotation of the actuating member moves the stem axially with respect tothe hanger and tubing head, and stop means on the upper end of the stemengageable with the upper end of the actuating member when the. stem isat its limit of downward movement, whereby a subsequent rotation of theactuating member in a direction tending to thread the step means towardthe actuating member eifects a simultaneous rotation of the member andstem.

8. A well head assembly as set forth in claim 7, together with anenlargement on the stem below the hanger and movable into sealingcontact with the lower end of the hanger to seal betwwn the stem andhanger and also to limit the upward movement of the stem.

- '9; A well head apparatus as set forth in claim '7, wherein thetubular hanger is formed with an external seating surface having sealingcontact with the seat within the tubing head.

10. A well head apparatus as set forth in claim '7, wherein the tubularhanger is formed with an external seating surface having sealing contactwith the seat within the tubing head, and also wherein said stem has anenlargement thereon below the hanger which enlargement is movable intosealing contact with the lower end of the hangerto seal between stem andhanger and also to limit the upward movement of the stem.

11. A well head apparatus as set forth in claim '7, together withradially extending locking means mounted within the tubing head andengageable with the hanger for locking said hanger on the seat withinthe head.

12.A well head apparatus including, a tubing head having an internalseat, a tubular hanger havingan external seating surface adapted toengage the seat with sealing contact, an annular actuating memberrotatably mounted on the upper end of the hanger, a sealing ring betweenthe upper end of the hanger and the tubing head sealing the jointtherebetween, a retaining flange secured to the upper end of the tubinghead engaging the sealing ring to retain it in position, a tubular stemextending axially through the actuating member and hanger and having itslower end connected to a well pipe, and coarse interengaging threadsbetween the member and stem whereby rotation of the member impartslongitudinal movement to the stem relative to the hanger and tubinghead.

13. A well head apparatus as set forth in claim 12, together with aflange on the upper end of the stem adapted to engage the upper end ofthe actuating member to limit downward movement of the stem with respectto the hanger, and an enlargement on the stem below the hanger'andmovable into sealing contact with the lower end of the hanger when thestem is moved to the limit of its upward movement with respect to thehanger.

14. A well head apparatus as set forth in claim 12, together with aclosure removably mounted. within the stem, to close the bore of thewell pipe to which the stem is connected.

CICERO C. BROWN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,896,236 Howard Feb. '7, 1933 1,902,540 Brown Mar. 21, 19331,944,840 Humason Jan. 23, 1934 2,134,044 Humason Oct. 25, 19382,139,207 Rector Dec. 6, 1938 2,145,844 Brown Feb. 7, 1939 2,157,964Mueller May 9, 1939

